//! Matrix room identifiers.

use diesel::expression::AsExpression;

use super::{
    MatrixToUri, MatrixUri, OwnedEventId, OwnedServerName, ServerName, matrix_uri::UriAction,
};
use crate::macros::IdDst;
use crate::{IdParseError, RoomOrAliasId};

/// A Matrix [room ID].
///
/// A `RoomId` is generated randomly or converted from a string slice, and can
/// be converted back into a string as needed.
///
/// ```
/// # use palpo_core::RoomId;
/// assert_eq!(<&RoomId>::try_from("!n8f893n9:example.com").unwrap(), "!n8f893n9:example.com");
/// ```
///
/// [room ID]: https://spec.matrix.org/latest/appendices/#room-ids
#[repr(transparent)]
#[derive(PartialEq, Eq, PartialOrd, Ord, Hash, IdDst, AsExpression)]
#[diesel(not_sized, sql_type = diesel::sql_types::Text)]
#[palpo_id(validate = palpo_identifiers_validation::room_id::validate)]
pub struct RoomId(str);

impl RoomId {
    /// Attempts to generate a `RoomId` for the given origin server with a localpart consisting of
    /// 18 random ASCII alphanumeric characters, as recommended in the spec.
    ///
    /// This generates a room ID matching the [`RoomIdFormatVersion::V1`] variant of the
    /// `room_id_format` field of [`RoomVersionRules`]. To construct a room ID matching the
    /// [`RoomIdFormatVersion::V2`] variant, use [`RoomId::new_v2()`] instead.
    ///
    /// [`RoomIdFormatVersion::V1`]: crate::room_version_rules::RoomIdFormatVersion::V1
    /// [`RoomIdFormatVersion::V2`]: crate::room_version_rules::RoomIdFormatVersion::V2
    /// [`RoomVersionRules`]: crate::room_version_rules::RoomVersionRules
    pub fn new_v1(server_name: &ServerName) -> OwnedRoomId {
        Self::from_borrowed(&format!("!{}:{server_name}", super::generate_localpart(18))).to_owned()
    }

    /// Construct an `OwnedRoomId` using the reference hash of the `m.room.create` event of the
    /// room.
    ///
    /// This generates a room ID matching the [`RoomIdFormatVersion::V2`] variant of the
    /// `room_id_format` field of [`RoomVersionRules`]. To construct a room ID matching the
    /// [`RoomIdFormatVersion::V1`] variant, use [`RoomId::new_v1()`] instead.
    ///
    /// Returns an error if the given string contains a NUL byte or is too long.
    ///
    /// [`RoomIdFormatVersion::V1`]: crate::room_version_rules::RoomIdFormatVersion::V1
    /// [`RoomIdFormatVersion::V2`]: crate::room_version_rules::RoomIdFormatVersion::V2
    /// [`RoomVersionRules`]: crate::room_version_rules::RoomVersionRules
    pub fn new_v2(room_create_reference_hash: &str) -> Result<OwnedRoomId, IdParseError> {
        Self::parse(format!("!{room_create_reference_hash}"))
    }

    /// Returns the room ID without the initial `!` sigil.
    ///
    /// For room versions using [`RoomIdFormatVersion::V2`], this is the reference hash of the
    /// `m.room.create` event of the room.
    ///
    /// [`RoomIdFormatVersion::V2`]: crate::room_version_rules::RoomIdFormatVersion::V2
    pub fn strip_sigil(&self) -> &str {
        self.as_str()
            .strip_prefix('!')
            .expect("sigil should be checked during construction")
    }

    /// Returns the server name of the room ID.
    pub fn server_name(&self) -> Result<&ServerName, &str> {
        <&RoomOrAliasId>::from(self).server_name()
    }

    /// Create a `matrix.to` URI for this room ID.
    ///
    /// Note that it is recommended to provide servers that should know the room
    /// to be able to find it with its room ID. For that use
    /// [`RoomId::matrix_to_uri_via()`].
    ///
    /// # Example
    ///
    /// ```
    /// use palpo_core::{room_id, server_name};
    ///
    /// assert_eq!(
    ///     room_id!("!somewhere:example.org").matrix_to_uri().to_string(),
    ///     "https://matrix.to/#/!somewhere:example.org"
    /// );
    /// ```
    pub fn matrix_to_uri(&self) -> MatrixToUri {
        MatrixToUri::new(self.into(), vec![])
    }

    /// Create a `matrix.to` URI for this room ID with a list of servers that
    /// should know it.
    ///
    /// To get the list of servers, it is recommended to use the [routing
    /// algorithm] from the spec.
    ///
    /// If you don't have a list of servers, you can use
    /// [`RoomId::matrix_to_uri()`] instead.
    ///
    /// # Example
    ///
    /// ```
    /// use palpo_core::{room_id, server_name};
    ///
    /// assert_eq!(
    ///     room_id!("!somewhere:example.org")
    ///         .matrix_to_uri_via([&*server_name!("example.org"), &*server_name!("alt.example.org")])
    ///         .to_string(),
    ///     "https://matrix.to/#/!somewhere:example.org?via=example.org&via=alt.example.org"
    /// );
    /// ```
    ///
    /// [routing algorithm]: https://spec.matrix.org/latest/appendices/#routing
    pub fn matrix_to_uri_via<T>(&self, via: T) -> MatrixToUri
    where
        T: IntoIterator,
        T::Item: Into<OwnedServerName>,
    {
        MatrixToUri::new(self.into(), via.into_iter().map(Into::into).collect())
    }

    /// Create a `matrix.to` URI for an event scoped under this room ID.
    ///
    /// Note that it is recommended to provide servers that should know the room
    /// to be able to find it with its room ID. For that use
    /// [`RoomId::matrix_to_event_uri_via()`].
    pub fn matrix_to_event_uri(&self, ev_id: impl Into<OwnedEventId>) -> MatrixToUri {
        MatrixToUri::new((self.to_owned(), ev_id.into()).into(), vec![])
    }

    /// Create a `matrix.to` URI for an event scoped under this room ID with a
    /// list of servers that should know it.
    ///
    /// To get the list of servers, it is recommended to use the [routing
    /// algorithm] from the spec.
    ///
    /// If you don't have a list of servers, you can use
    /// [`RoomId::matrix_to_event_uri()`] instead.
    ///
    /// [routing algorithm]: https://spec.matrix.org/latest/appendices/#routing
    pub fn matrix_to_event_uri_via<T>(&self, ev_id: impl Into<OwnedEventId>, via: T) -> MatrixToUri
    where
        T: IntoIterator,
        T::Item: Into<OwnedServerName>,
    {
        MatrixToUri::new(
            (self.to_owned(), ev_id.into()).into(),
            via.into_iter().map(Into::into).collect(),
        )
    }

    /// Create a `matrix:` URI for this room ID.
    ///
    /// If `join` is `true`, a click on the URI should join the room.
    ///
    /// Note that it is recommended to provide servers that should know the room
    /// to be able to find it with its room ID. For that use
    /// [`RoomId::matrix_uri_via()`].
    ///
    /// # Example
    ///
    /// ```
    /// use palpo_core::{room_id, server_name};
    ///
    /// assert_eq!(
    ///     room_id!("!somewhere:example.org").matrix_uri(false).to_string(),
    ///     "matrix:roomid/somewhere:example.org"
    /// );
    /// ```
    pub fn matrix_uri(&self, join: bool) -> MatrixUri {
        MatrixUri::new(self.into(), vec![], Some(UriAction::Join).filter(|_| join))
    }

    /// Create a `matrix:` URI for this room ID with a list of servers that
    /// should know it.
    ///
    /// To get the list of servers, it is recommended to use the [routing
    /// algorithm] from the spec.
    ///
    /// If you don't have a list of servers, you can use
    /// [`RoomId::matrix_uri()`] instead.
    ///
    /// If `join` is `true`, a click on the URI should join the room.
    ///
    /// # Example
    ///
    /// ```
    /// use palpo_core::{room_id, server_name};
    ///
    /// assert_eq!(
    ///     room_id!("!somewhere:example.org")
    ///         .matrix_uri_via(
    ///             [&*server_name!("example.org"), &*server_name!("alt.example.org")],
    ///             true
    ///         )
    ///         .to_string(),
    ///     "matrix:roomid/somewhere:example.org?via=example.org&via=alt.example.org&action=join"
    /// );
    /// ```
    ///
    /// [routing algorithm]: https://spec.matrix.org/latest/appendices/#routing
    pub fn matrix_uri_via<T>(&self, via: T, join: bool) -> MatrixUri
    where
        T: IntoIterator,
        T::Item: Into<OwnedServerName>,
    {
        MatrixUri::new(
            self.into(),
            via.into_iter().map(Into::into).collect(),
            Some(UriAction::Join).filter(|_| join),
        )
    }

    /// Create a `matrix:` URI for an event scoped under this room ID.
    ///
    /// Note that it is recommended to provide servers that should know the room
    /// to be able to find it with its room ID. For that use
    /// [`RoomId::matrix_event_uri_via()`].
    pub fn matrix_event_uri(&self, ev_id: impl Into<OwnedEventId>) -> MatrixUri {
        MatrixUri::new((self.to_owned(), ev_id.into()).into(), vec![], None)
    }

    /// Create a `matrix:` URI for an event scoped under this room ID with a
    /// list of servers that should know it.
    ///
    /// To get the list of servers, it is recommended to use the [routing
    /// algorithm] from the spec.
    ///
    /// If you don't have a list of servers, you can use
    /// [`RoomId::matrix_event_uri()`] instead.
    ///
    /// [routing algorithm]: https://spec.matrix.org/latest/appendices/#routing
    pub fn matrix_event_uri_via<T>(&self, ev_id: impl Into<OwnedEventId>, via: T) -> MatrixUri
    where
        T: IntoIterator,
        T::Item: Into<OwnedServerName>,
    {
        MatrixUri::new(
            (self.to_owned(), ev_id.into()).into(),
            via.into_iter().map(Into::into).collect(),
            None,
        )
    }
}

// #[cfg(test)]
// mod tests {
//     use super::{OwnedRoomId, RoomId};
//     use crate::{server_name, IdParseError};

//     #[test]
//     fn valid_room_id() {
//         let room_id =
// <&RoomId>::try_from("!29fhd83h92h0:example.com").expect("Failed to create
// RoomId.");         assert_eq!(room_id, "!29fhd83h92h0:example.com");
//     }

//     #[test]
//     fn empty_localpart() {
//         let room_id = <&RoomId>::try_from("!:example.com").expect("Failed to
// create RoomId.");         assert_eq!(room_id, "!:example.com");
//         assert_eq!(room_id.server_name(), Some(server_name!("example.com")));
//     }

//     #[test]
//     fn generate_random_valid_room_id() {
//         let room_id = RoomId::new(server_name!("example.com"));
//         let id_str = room_id.as_str();

//         assert!(id_str.starts_with('!'));
//         assert_eq!(id_str.len(), 31);
//     }

//     #[test]
//     fn serialize_valid_room_id() {
//         assert_eq!(
//
// serde_json::to_string(<&RoomId>::try_from("!29fhd83h92h0:example.com").
// expect("Failed to create RoomId."))                 .expect("Failed to
// convert RoomId to JSON."),             r#""!29fhd83h92h0:example.com""#
//         );
//     }

//     #[test]
//     fn deserialize_valid_room_id() {
//         assert_eq!(
//
// serde_json::from_str::<OwnedRoomId>(r#""!29fhd83h92h0:example.com""#)
//                 .expect("Failed to convert JSON to RoomId"),
//             <&RoomId>::try_from("!29fhd83h92h0:example.com").expect("Failed
// to create RoomId.")         );
//     }

//     #[test]
//     fn valid_room_id_with_explicit_standard_port() {
//         let room_id =
// <&RoomId>::try_from("!29fhd83h92h0:example.com:443").expect("Failed to create
// RoomId.");         assert_eq!(room_id, "!29fhd83h92h0:example.com:443");
//         assert_eq!(room_id.server_name(),
// Some(server_name!("example.com:443")));     }

//     #[test]
//     fn valid_room_id_with_non_standard_port() {
//         assert_eq!(
//
// <&RoomId>::try_from("!29fhd83h92h0:example.com:5000").expect("Failed to
// create RoomId."),             "!29fhd83h92h0:example.com:5000"
//         );
//     }

//     #[test]
//     fn missing_room_id_sigil() {
//         assert_eq!(
//             <&RoomId>::try_from("carl:example.com").unwrap_err(),
//             IdParseError::MissingLeadingSigil
//         );
//     }

//     #[test]
//     fn missing_server_name() {
//         let room_id = <&RoomId>::try_from("!29fhd83h92h0").expect("Failed to
// create RoomId.");         assert_eq!(room_id, "!29fhd83h92h0");
//         assert_eq!(room_id.server_name(), None);
//     }

//     #[test]
//     fn invalid_room_id_host() {
//         let room_id = <&RoomId>::try_from("!29fhd83h92h0:/").expect("Failed
// to create RoomId.");         assert_eq!(room_id, "!29fhd83h92h0:/");
//         assert_eq!(room_id.server_name(), None);
//     }

//     #[test]
//     fn invalid_room_id_port() {
//         let room_id =
// <&RoomId>::try_from("!29fhd83h92h0:example.com:notaport").expect("Failed to
// create RoomId.");         assert_eq!(room_id,
// "!29fhd83h92h0:example.com:notaport");         assert_eq!(room_id.
// server_name(), None);     }
// }
